public class Solution
extends Object
1525 - Number of Good Ways to Split a String\.
Medium
You are given a string `s`.
A split is called **good** if you can split `s` into two non-empty strings sleft and sright where their concatenation is equal to `s` (i.e., sleft + sright = s) and the number of distinct letters in sleft and sright is the same.
Return _the number of **good splits** you can make in `s`_.
**Example 1:**
**Input:** s = "aacaba"
**Output:** 2
**Explanation:** There are 5 ways to split `"aacaba"` and 2 of them are good.
("a", "acaba") Left string and right string contains 1 and 3 different letters respectively.
("aa", "caba") Left string and right string contains 1 and 3 different letters respectively.
("aac", "aba") Left string and right string contains 2 and 2 different letters respectively (good split).
("aaca", "ba") Left string and right string contains 2 and 2 different letters respectively (good split).
("aacab", "a") Left string and right string contains 3 and 1 different letters respectively.
**Example 2:**
**Input:** s = "abcd"
**Output:** 1
**Explanation:** Split the string as follows ("ab", "cd").
**Constraints:**
* 1 <= s.length <= 105
* `s` consists of only lowercase English letters.